The methods for constructing aquatic structures make use, normally, of premanufactured foundations. Said foundations are manufactured, at least for the most part, far from the installation site of the foundation, being transported to said site in a floating manner, either in a self-floating manner or with assistance from separate flotation means (barges, tugs, floats, etc.), and being installed by means of sinking in the underwater bed.
One type of premanufactured foundation, compatible with the present invention, is the gravity foundation, wherein the foundation comprises a solid or hollow body, optionally weighed down, which is stably installed on the underwater bed by the effects of, at least mainly, the very weight thereof and/or the weight of the ballast thereof, if appropriate.
Scouring is the removal of materials from an underwater bed due to the erosive effects of the water flow around an element arranged in such an underwater bed.
Aquatic infrastructures, and especially marine infrastructures, are, during the useful life thereof, simultaneously subjected to the effects of currents, waves and tides. The result of the interaction between the water flow and the foundation of the infrastructures creates the scouring phenomenon. The appearance of this phenomenon around a foundation can cause the scouring thereof, which represents a very significant problem for the stability of the structure on top.
In order to prevent or at least reduce the scouring around a foundation, the technique of laying anti-scouring material on the area susceptible to undergoing such a phenomenon is known. The anti-scouring material tends to be, for example, gravel or rockfill that is transported in barges and, once the foundation is installed, is placed around the foundation by means of cranes, for example ladle cranes, or by means of pouring machines. Placing anti-scouring material in an installation site of a foundation prior to the installation of the foundation is also known. In any case, it is a technique used with the construction methods that make use of premanufactured foundations.